Fluid shutter for light-projecting apparatus



Oct. 16, 1951 J. D. KENNELLY 2,571,894

FLUID SHUTTER FOR LIGHT-PROJECTING APPARATUS Filed March 12, 1948 within a casing 2I.

Patented Oct. 16, 1951 FLUID SHUTTER FOR LIGHTPPROJECTING APPARATUS .t'eremiah D. Kennelly, Oak Park, Ill.

Application March 12, 1948, Serial No. 14,574

1 Claim. 1

This invention relates to a fluid shutter for light-projecting apparatus. The invention is particularly useful in conjunction with the headlights or illumination lights of locomotives,

train lights and lights used with emergency vehicles, aeroplanes, vessels, and other moving vehicles.

An object of the invention is to provide a fluid shutter elfective for converting the illuminating rays from a searchlight, headlight or other light source into a warning light, etc. A further object is to provide a simple device which may be operated manually or automatically upon the drop in pressure in a brake pipe for the changing of projected light beams into warning light beams, etc., or into beams of various other colors for different purposes. Other specific objects and advantages will appear as the specification proceeds.

The invention is illustrated, in a single embodiment, by the accompanying drawing, in which- Figure 1 is a side view in elevation of apparatus embodying my invention, the valve structure being shown in section; Fig. 2, a top plan view; and Fig. 3, an enlarged transverse sectional view of the fluid shutter, the shutter be-.

ing shown in a preferred arrangement in front of a light source.

In the illustration given, I!) designates a reservoir tank, preferably closed at its top and with a conduit II leading to the bottom of a fluid filter I2. The fluid filter may be formed of any desired material and in any desired configuration.

In the illustration given, I provide a cylindrical frame I3 receiving therein, in spaced relation, the transparent plates I4 formed of glass, plastic or other suitable material, and providing between them a fluid chamber I5 adapted to receive a translucent colored fluid. The frame I3 is preferably provided with a ring I6 of resilient material, such as, for example, rubber, and with annular slots formed therein to receive the plates I4.

A conduit I'I leaves the top of the fluid shutter I2 and passes through a solenoid-operated valve I8. In the illustration given, the valve I8 consists of a rotary plug member I9, having a passage 26 extending therethrough, and received The casing ZI is provided with an outlet vent 22 and with an outlet receiving a pipe 23 leading to the compressed air brake conduit, or to any other source of air pressure. The valve plug I9 may be rotated by hand or, as illustrated, it may be rotated by a solenoid 2 u. By rotating the valve plug IS, the passage 20 therein may be brought into communication with the vent 22 or, alternatively, into communication with the brake pipe 23, as shown more clearly in Fig. 1.

The fluid filter may be located in front of the Searchlight, headlight, train light, or any other light source which is ordinarily used for projeoting light beams, and the passage of colored fluid into the chamber I5 brings about a change in the color of the projected light rays.

Any red liquid, which is pervious to the light rays, may be employed. Water colored red, or any other desired color, may be used. In order to avoid freezing of the liquid, any of the wellknown liquids which do not freeze at low tem peratures, may be used for this purpose, and any suitable coloring material may be employed.

In the specific illustration given, when the valve plug I9 is turned to the position illustrated in Fig. 1, compressed air from the brake pipe 23 passes through the valve, pipe I7, and fluid shutter I2, and forces the colored fluid out of chamber I5 and back through pipe II into the reservoir tank It. The liquid is pressed upwardly in the tank I0 so as to compress the air trapped therein within the space indicated by the numeral 25.

The light source, which may be of any suitable type, is at this point effective merely for illumination purposes. In Fig. 3, a light-projecting casing 26, equipped with a light bulb 21, is located behind the fluid shutter I2, and when the chamber I5 is open, the light rays pass, without modification, through the transparent panes I4.

When it is desired to render the shutter operative for screening out the light rays or for changing their color, the valve plug I9 is rotated to bring the passage 20 into communication with the vent 22 and pipe I I. Upon the escape of the compressed air, the liquid within reservoir I0 will pass rapidly downwardly through pipe II and upwardly into chamber I5 to substantially fill the chamber. The latter movement of the liquid is accelerated by reason 01 the pressure exerted by the trapped air in space 25 of tank I 13. The light rays now projected through the panes I 4 and the body of fluid are changed in color. If a red fluid should be employed, the rays will thus become warning rays, etc.

As above stated, the valve plug 19 may be rotated manually or by actuating the solenoid 24. Further, if pipe 23 is connected to a brake pressure line and the pressure falls below a predetermined limit, the liquid will flow against the reduced pressure upwardly into the chamber I of the fluid shutter I2 so as to automatically convert the projected light rays into warning rays.

While, in the foregoing specification, I have shown a single structure and described the same in considerable detail, it will be understood that the details of such structure may be varied widely by those skilled in the art without departing from the spirit of my invention.

I claim:

In combination with a light source carried by a vehicle equipped with a compressed air line, the compressed air line being used for setting brakes, a fluid shutter mounted in front of said light source and equipped with transparent plates providing a chamber between them adapted to receive a colored fluid, an air-tight reservoir adapted to receive said colored fluid, a conduit connecting said reservoir and said chamber, means supporting said reservoir at a level at least equal to that of said chamber, a valve casing equipped with a vent outlet, an outlet conduit communicating with the compressed air line, and

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 708,365 Kligel Sept. 2, 1902 2,165,488 Klimis July 11, 1939 FOREIGN PATENTS Number Country Date 303,236 Great Britain 1929 608,867 France 1926 613.587 France 1926 

